Smoking more than 20 cigarettes a day may affect colour vision

New research has highlighted the impact of heavy smoking on an individual’s colour vision.

Writing in Psychiatry Research, scientists report on a study of 71 people who smoked fewer than 15 cigarettes in their lives and 63 smokers.

The smokers featured in the research smoked more than 20 cigarettes a day, were diagnosed with tobacco addiction and had not made attempts to stop smoking.

All participants were aged between the ages of 25 and 45 and had normal vision as measured by standard acuity charts.

The researchers tested how study participants discriminated between differences in colour and contrast.

They found that the smokers had significant changes in their red-green and blue-yellow colour vision, with a reduced ability to differentiate between contrast and colours when compared to non-smokers.

Co-author, Steven Silverstein, director of research at Rutgers University Behavioral Health Care in the US, highlighted that previous research has connected long-term smoking with doubling the risk for age-related macular degeneration and as a factor in the yellowing and inflammation of the lens.

“Our results indicate that excessive use of cigarettes, or chronic exposure to their compounds, affects visual discrimination, supporting the existence of overall deficits in visual processing with tobacco addiction,” he shared.